48 results on '"Ayumi Ogawa"'
Search Results
2. Development and validation of a pre- and intra-operative scoring system that distinguishes between non-advanced and advanced axillary lymph node metastasis in breast cancer with positive sentinel lymph nodes: a retrospective study
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Takeshi Murata, Chikashi Watase, Sho Shiino, Arisa Kurita, Ayumi Ogawa, Kenjiro Jimbo, Eriko Iwamoto, Masayuki Yoshida, Shin Takayama, and Akihiko Suto
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Breast cancer ,Prediction of advanced lymph node metastasis ,Scoring system ,Sentinel lymph node metastasis ,Preoperative ,Surgery ,RD1-811 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background There are currently no scoring-type predictive models using only easily available pre- and intraoperative data developed for assessment of the risk of advanced axillary lymph node metastasis (ALNM) in patients with breast cancer with metastatic sentinel lymph nodes (SLNs). We aimed to develop and validate a scoring system using only pre- and intraoperative data to distinguish between non-advanced (≤ 3 lymph nodes) and advanced (> 3 lymph nodes) ALNM in patients with breast cancer with metastatic SLNs. Methods We retrospectively identified 804 patients with breast cancer (cT1-3cN0) who had metastatic SLNs and had undergone axillary lymph node dissection (ALND). We evaluated the risk factors for advanced ALNM using logistic regression analysis and developed and validated a scoring system for the prediction of ALNM using training (n = 501) and validation (n = 303) cohorts, respectively. The predictive performance was assessed using the receiver operating characteristic (ROC) curve, area under the curve (AUC), and calibration plots. Results Ultrasound findings of multiple suspicious lymph nodes, SLN macrometastasis, the ratio of metastatic SLNs to the total number of SLNs removed, and the number of metastatic SLNs were significant risk factors for advanced ALNM. Clinical tumor size and invasive lobular carcinoma were of borderline significance. The scoring system based on these six variables yielded high AUCs (0.90 [training] and 0.89 [validation]). The calibration plots of frequency compared to the predicted probability showed slopes of 1.00 (training) and 0.85 (validation), with goodness-of-fit for the model. When the cutoff score was set at 4, the negative predictive values (NPVs) of excluding patients with advanced ALNM were 96.8% (training) and 96.9% (validation). The AUC for predicting advanced ALNM using our scoring system was significantly higher than that predicted by a single independent predictor, such as the number of positive SLNs or the proportion of positive SLNs. Similarly, our scoring system also showed good discrimination and calibration ability when the analysis was restricted to patients with one or two SLN metastases. Conclusion Our easy-to-use scoring system can exclude advanced ALNM with high NPVs. It may contribute to reducing the risk of undertreatment with adjuvant therapies in patients with metastatic SLNs, even if ALND is omitted.
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- 2022
- Full Text
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3. Bone Marrow Carcinomatosis in a Stage IV Breast Cancer Patient Treated by Letrozole as First-Line Endocrine Therapy
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Tsuyoshi Nakagawa, Kumiko Hayashi, Ayumi Ogawa, Goshi Oda, Iichiro Onishi, Masahide Yamamoto, Mio Mori, Tomoyuki Fujioka, Toshiaki Ishikawa, Kentaro Okamoto, and Hiroyuki Uetake
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breast cancer ,bone marrow carcinomatosis ,endocrine therapy ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Bone marrow carcinomatosis (BMC) associated with breast cancer is a rare but often difficult-to-treat condition; we report a case of a female stage IV breast cancer patient in her seventies with BMC that improved with endocrine monotherapy. The patient had hemoglobinopenia and thrombocytopenia at the time of diagnosis. The diagnosis of BMC due to estrogen receptor-positive invasive lobular carcinoma was confirmed. After transfusion of 4 units of concentrated red blood cells, endocrine treatment with letrozole improved the hematopenia. Ten months after the treatment started, bone metastases worsened, so the patient was changed to combination therapy with palbociclib and fulvestrant, after which there was no worsening of the disease.
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- 2022
- Full Text
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4. Spontaneous regression of breast lymphoproliferative disorders after withdrawal of methotrexate in rheumatoid arthritis patients with Epstein–Barr virus infection: a case report and review of the literature
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Ayumi Ogawa, Tsuyoshi Nakagawa, Yuichi Kumaki, Tokuko Hosoya, Goshi Oda, Mio Mori, Tomoyuki Fujioka, Kazunori Kubota, Iichiro Onishi, and Hiroyuki Uetake
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Methotrexate-associated lymphoproliferative disorders (MTX-LPD) ,Other iatrogenic immunodeficiency-associated lymphoproliferative disorders (OIIA-LPD) ,Breast lymphoma ,Epstein–Barr virus (EBV) ,Medicine - Abstract
Abstract Background Lymphoproliferative disorder (LPD) has been shown to occur after treatment with methotrexate (MTX). Currently, MTX-LPD has become widely recognized, but its mechanism and prognostic factors remain unclear. Case presentation We report the first case of Epstein–Barr virus (EBV)-associated MTX-LPD of the breast. A 63-year-old Asian woman with long-term rheumatoid arthritis presented to our facility with intermittent fever. A physical examination revealed a 3-cm lump in her left breast. She had been taking MTX for the past 15 years. Laboratory studies revealed slightly elevated levels of EBV-viral capsid antigen antibody immunoglobulin G and EBV nuclear antibody. Contrast-enhanced computer tomography revealed a mass in the left breast, a subcutaneous nodule in the abdomen, a mass in the left lung, and a nodule in the left retroperitoneum. The definitive diagnosis was consistent with MTX-LPD merging into an EBV-positive, diffuse large B-cell lymphoma. Six months following the withdrawal of MTX, the breast mass had markedly shrunk and the patient remained in good health for 1 year with no evidence of relapse of LPD. Conclusion MTX-LPD rarely occurs in the breast, and it is difficult to diagnose because there have only been six reported cases of breast MTX-LPD reported in the literature. EBV-positive MTX-LPD tends to regress spontaneously after MTX withdrawal, and our case also had similar results. It is important to make an appropriate diagnosis of MTX-LPD of the breast based on imaging and pathology to determine the appropriate treatment protocol for this rare disorder.
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- 2022
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5. Hydronephrosis Caused by Metastatic Breast Cancer
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Hitoshi Sugimoto, Goshi Oda, Minato Yokoyama, Kumiko Hayashi, Maho Yoshino, Ayumi Ogawa, Tokuko Hosoya, Tsuyoshi Nakagawa, and Hiroyuki Uetake
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hydronephrosis ,breast cancer ,metastasis ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Breast cancer metastasizes mainly to organs such as bone, lung, and liver, whereas metastases to the peritoneum and urinary tract are rare. Metastasis to the peritoneum or urinary tract may result in renal dysfunction, infection, and painful hydronephrosis. In our hospital, 1,409 breast cancer surgeries were performed between January 2004 and December 2015, and 7 cases of hydronephrosis associated with recurrence were observed. The median age of patients was 69 years (57–79 years). The median time from surgery to diagnosis of hydronephrosis was 47 months (20–70 months). Histology was invasive ductal carcinoma (IDC) in 6 cases and invasive lobular carcinoma (ILC) in 1 case. There were 6 bilateral cases and 1 unilateral case of hydronephrosis. The causes were retroperitoneal metastasis in 5 cases and lymph node metastasis in 2 cases. The hydronephrosis was untreated in 2 cases, and treated with a ureteral stent in 2 cases, nephrostomy in 1 case, and nephrostomy due to ureteral stent failure in 2 cases. The median survival from the onset of hydronephrosis was 12 months (3–57 months). Although the probability of hydronephrosis in breast cancer recurrence was not high, care must be taken to avoid renal dysfunction, infection, or pain, which may require treatment.
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- 2021
- Full Text
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6. A prediction model for distant metastasis after isolated locoregional recurrence of breast cancer
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Takeshi Murata, Masayuki Yoshida, Sho Shiino, Ayumi Ogawa, Chikashi Watase, Kaishi Satomi, Kenjiro Jimbo, Akiko Maeshima, Eriko Iwamoto, Shin Takayama, and Akihiko Suto
- Subjects
Cancer Research ,Oncology - Abstract
Purpose The impact of progesterone receptor (PR) status on the prognosis of breast cancer after isolated locoregional recurrence (ILRR) remains unclear. This study evaluated the impact of clinicopathologic factors, including PR status of ILRR, on distant metastasis (DM) after ILRR. Methods We retrospectively identified 306 patients with ILRR diagnosed at the National Cancer Center Hospital between 1993 and 2021 from the database. Cox proportional hazards analysis was performed to examine factors associated with DM after ILRR. We developed a risk prediction model based on the number of detected risk factors and estimated survival curves using the Kaplan–Meier method. Results During a median follow-up time of 4.7 years after ILRR diagnosis, 86 patients developed DM, and 50 died. Multivariate analysis revealed that seven risk factors were associated with poor distant metastasis-free survival (DMFS): estrogen receptor-positive/PR-negative/human epidermal growth factor receptor 2-negative ILRR, short disease-free interval, recurrence site other than ipsilateral breast, no-resection of ILRR tumor, chemotherapy for the primary tumor, nodal stage in the primary tumor, and no endocrine therapy for ILRR. The predictive model classified patients into 4 groups based on the number of risk factors: low-, intermediate-, high-, and the highest-risk groups with 0 to 1, 2, 3 to 4, and 5 to 7 factors, respectively. This revealed significant variation in DMFS among the groups. A higher number of the risk factors was associated with poorer DMFS. Conclusion Our prediction model, which considered the ILRR receptor status, may contribute to the development of a treatment strategy for ILRR.
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- 2023
7. Disclosure of presentations and discussions from the perspective of 'Academic Camp 2021 in Oshu'
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Ayumi OGAWA, Misato HORII, Hiroshi HORII, Sakiko KAWABE, Makoto GOTO, and Yoshihiro TAKATA
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- 2021
8. A Study on the Construction of Digital Archives in Cooperation with University Museum and Company -A Case of Digital Archives on Nature and Science Museum, Tokyo University of Agriculture and Technology-
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Hiroshi HORII, Ayumi OGAWA, Misato HORII, Yurika SAITO, Takeshi YOKOYAMA, and Keiichi KANEKO
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- 2021
9. Construction and Issues of the 'Model for Inheritance and Recording of Information on Regional Materials'
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Misato HORII, Ayumi OGAWA, Hiroshi HORII, Kazutaka TAKAHASHI, Kohei NOZAKA, Sakiko KAWABE, and Makoto GOTO
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- 2021
10. Hydronephrosis Caused by Metastatic Breast Cancer
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Goshi Oda, Hitoshi Sugimoto, Maho Yoshino, Ayumi Ogawa, Kumiko Hayashi, Tsuyoshi Nakagawa, Hiroyuki Uetake, Tokuko Hosoya, and Minato Yokoyama
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medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Urinary system ,Stent ,Case Report ,medicine.disease ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,Metastatic breast cancer ,lcsh:RC254-282 ,Metastasis ,Breast cancer ,breast cancer ,Oncology ,hydronephrosis ,Invasive lobular carcinoma ,Nephrostomy ,medicine ,metastasis ,Radiology ,business ,Hydronephrosis - Abstract
Breast cancer metastasizes mainly to organs such as bone, lung, and liver, whereas metastases to the peritoneum and urinary tract are rare. Metastasis to the peritoneum or urinary tract may result in renal dysfunction, infection, and painful hydronephrosis. In our hospital, 1,409 breast cancer surgeries were performed between January 2004 and December 2015, and 7 cases of hydronephrosis associated with recurrence were observed. The median age of patients was 69 years (57–79 years). The median time from surgery to diagnosis of hydronephrosis was 47 months (20–70 months). Histology was invasive ductal carcinoma (IDC) in 6 cases and invasive lobular carcinoma (ILC) in 1 case. There were 6 bilateral cases and 1 unilateral case of hydronephrosis. The causes were retroperitoneal metastasis in 5 cases and lymph node metastasis in 2 cases. The hydronephrosis was untreated in 2 cases, and treated with a ureteral stent in 2 cases, nephrostomy in 1 case, and nephrostomy due to ureteral stent failure in 2 cases. The median survival from the onset of hydronephrosis was 12 months (3–57 months). Although the probability of hydronephrosis in breast cancer recurrence was not high, care must be taken to avoid renal dysfunction, infection, or pain, which may require treatment.
- Published
- 2021
11. Report on '2020 Academic Camp in Oshu City' Online tour : Research meeting in the age of COVID-19 pandemic
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Sakiko Kawabe, Hiroshi Horii, Yoshihiro Takata, Misato Horii, Makoto Goto, and Ayumi Ogawa
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- 2021
12. Information sharing and disclosure of regional materials survey in the age of COVID-19 pandemic: A case study in Oshu City, Iwate Prefecture
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Sakiko Kawabe, Ayumi Ogawa, Hiroshi Horii, Shoko Terao, Misato Horii, Makoto Goto, Kohei Nozaka, and Kazutaka Takahashi
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- 2021
13. An Attempt at a Cultural Use of Social Distancing Spacein the Corona Disaster - A Case of KITEN Project
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Ryosuke Harashima, Ayumi Ogawa, Hiroshi Horii, and Misato Horii
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Social distance ,Environmental ethics ,Sociology - Published
- 2021
14. A Case of Breast Cancer with a Peculiar Invasive Pattern within a Fibroadenoma
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Ayumi Ogawa, Tsuyoshi Nakagawa, Mai Kasahara, Tokuko Hosoya, Tomoyuki Fujioka, Maho Yoshino, Goshi Oda, and Iichiro Onishi
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Oncology ,medicine.medical_specialty ,Breast cancer ,business.industry ,Internal medicine ,General Engineering ,medicine ,General Earth and Planetary Sciences ,business ,medicine.disease ,Fibroadenoma ,General Environmental Science - Published
- 2021
15. Predictors for upstaging of ductal carcinoma in situ (DCIS) to invasive carcinoma in non‑mass‑type DCIS
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Tokuko Hosoya, Hitoshi Sugimoto, Iichiroh Onishi, Goshi Oda, Toshiyuki Ishiba, Yuichi Kumaki, Mori Mio, Tsuyoshi Nakagawa, Tomoyuki Fujioka, Ayumi Ogawa, Hiroyuki Uetake, and Kazunori Kubota
- Subjects
Breast biopsy ,Cancer Research ,Univariate analysis ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Cancer ,Odds ratio ,Ductal carcinoma ,medicine.disease ,Palpation ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Oncology ,030220 oncology & carcinogenesis ,Ductal carcinoma in situ (DCIS) ,medicine ,030211 gastroenterology & hepatology ,Radiology ,skin and connective tissue diseases ,business - Abstract
Preoperatively diagnosed ductal carcinoma in situ (DCIS) is sometimes upstaged to invasive cancer by postoperative pathological examination. Various preoperative factors associated with upstaging to invasive cancer have been reported; however, this subject remains to be clarified. DCIS takes various forms on imaging, but many cases show non-mass-type lesions. In non-mass-type DCIS, recognizing the presence of invasion is difficult. To investigate predictors associated with upstaging to invasive cancer more precisely, we examined only non-mass-type DCIS. The present study retrospectively analyzed 101 patients diagnosed with non-mass-type DCIS preoperatively on breast biopsy at our institution between 2007 and 2017. Data were analyzed using Fisher's exact probability test and two-sample t-tests. Multivariate analysis was performed using logistic regression. The results showed that 27 patients (27%) were finally diagnosed with invasive cancer. Univariate analysis revealed abnormal result of palpation on breast examination (P=0.05), comedo necrosis (P=0.05), and HER2 status (P=0.02) as significant predictors. Multivariate analysis revealed an abnormal result of palpation as an independent predictor of invasive cancer underestimation (odds ratio 4.76; confidence interval 1.44-15.7; P=0.01). In conclusion, preoperatively diagnosed non-mass-type DCIS represented an underestimation in approximately 27% of cases. In particular, the presence of a clinically abnormal palpation increases the chance of upstaging to invasive cancer.
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- 2020
16. [A Case of Ramucirumab-Related Small Intestinal Perforation in Gastric Cancer]
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Hideaki, Murase, Ryo, Oono, Tsuyoshi, Yoshida, Kei, Ishihara, Mayuko, Otomo, Yuta, Suzuki, Kumiko, Hayashi, Kyoko, Higuchi, Satoshi, Yoshinouchi, Ayako, Kamiya, Mitsuru, Obata, Ayumi, Ogawa, Mikiko, Hayashi, Seongjin, Park, and Hideaki, Iseki
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Male ,Gastrectomy ,Intestinal Perforation ,Stomach Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Humans ,Middle Aged ,Antibodies, Monoclonal, Humanized - Abstract
A 54-year-old man underwent laparoscopic distal gastrectomy with D2 lymph node dissection and ante-colic Roux-en-Y reconstruction for gastric cancer. The histopathological diagnosis was pT2N3aM0, pStage ⅢA, HER2 negative. After 8 courses of S-1 plus oxaliplatin as adjuvant chemotherapy, he was diagnosed as peritoneal dissemination and treated with ramucirumab(RAM)plus paclitaxel(PTX). On the 12th day of course 10, he visited to our hospital with abdominal pain. CT showed free air and massive ascites. Emergent surgery was performed under the diagnosis of gastrointestinal perforation. A small intestinal perforation in front of the jejunal limb near gastric-jejunal anastomosis was identified and there was no peritoneal dissemination. We performed partial resection of remnant stomach and jejunal limb by linear stapler and reconstruction by end to side gastric-jejunal anastomosis. Because the gastric and intestinal wall were quite fragile and RAM impaired wound healing as adverse event, we feared about leakage, but he had no major postoperative complications and discharged on the 33th day after surgery. After 24 courses of nivolumab as third-line chemotherapy, the peritoneal dissemination disappeared. He has been alive without recurrence for about 1 year since then.
- Published
- 2022
17. Time dependence of multi-ion absorption into human enamel from surface prereacted glass-ionomer (S-PRG) filler eluate
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Motohiro Uo, Yoshiyuki Mori, Ayumi Ogawa, and Takahiro Wada
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Filler (packaging) ,Materials science ,0206 medical engineering ,Glass ionomer cement ,02 engineering and technology ,Dental Caries ,Ion ,03 medical and health sciences ,0302 clinical medicine ,stomatognathic system ,medicine ,Humans ,Dental Enamel ,General Dentistry ,Ions ,Enamel paint ,Elution ,030206 dentistry ,Tooth enamel ,020601 biomedical engineering ,stomatognathic diseases ,medicine.anatomical_structure ,Glass Ionomer Cements ,visual_art ,Inductively coupled plasma atomic emission spectroscopy ,Ceramics and Composites ,visual_art.visual_art_medium ,Absorption (chemistry) ,Nuclear chemistry - Abstract
Ion incorporation into the tooth is expected to be effective for caries prevention. Time-dependent ion incorporation released from surface pre-reacted glass-ionomer (S-PRG) filler eluate into tooth enamel was estimated by using inductively coupled plasma atomic emission spectroscopy (ICP-AES). Al, B, and Sr contents in enamel were increased in a time-dependent manner with immersion in S-PRG eluate. Clear ion incorporation was observed after 1 h of immersion in S-PRG filler eluate. Sr showed remarkable incorporation in enamel -up to 7,900 ppm- after 28 days of immersion. Sr and B incorporation rapidly occurred in S-PRG filler eluate, compared with their single component solutions. Simultaneous incorporation of cations and anions from S-PRG eluate occurred under balanced charge and may assist in rapid ion incorporation. Thus, various useful ions could be effectively incorporated into tooth enamel by applying S-PRG filler or its eluate; a bioactive effect can be expected.
- Published
- 2019
18. A Case of Laparoscopic Partial Cecal Resection for Stump Appendicitis
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Atsushi Fukuuchi, Mikiko Hayashi, Hideaki Iseki, Ayumi Ogawa, SeongJin Park, and Hideaki Murase
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medicine.medical_specialty ,business.industry ,medicine ,medicine.disease ,business ,Appendicitis ,Resection ,Surgery - Published
- 2019
19. A Case of Gastric Large Cell Endocrine Carcinoma
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Mikiko Hayashi, Hideaki Iseki, Hideaki Murase, Kenichi Kamachi, Ayumi Ogawa, and SeongJin Park
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Endocrine carcinoma ,business.industry ,Large cell ,Cancer research ,Medicine ,business - Published
- 2019
20. Study of the protocol used to evaluate skin-flap perfusion in mastectomy based on the characteristics of indocyanine green
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Noriko Uemura, Tomoyuki Fujioka, Kimihiro Igari, Tsuyoshi Nakagawa, Ayumi Ogawa, Kumiko Hayashi, Maho Yoshino, Hiroki Mori, Iichiroh Onishi, Tokuko Hosoya, Mio Mori, Hiroyuki Uetake, and Goshi Oda
- Subjects
Indocyanine Green ,medicine.medical_specialty ,Necrosis ,medicine.medical_treatment ,030303 biophysics ,Biophysics ,Breast Neoplasms ,Dermatology ,030207 dermatology & venereal diseases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Adjuvant therapy ,Medicine ,Humans ,Pharmacology (medical) ,Coloring Agents ,Mastectomy ,Retrospective Studies ,0303 health sciences ,Photosensitizing Agents ,business.industry ,Retrospective cohort study ,Perfusion ,Plastic surgery ,Oncology ,chemistry ,Photochemotherapy ,Female ,Radiology ,medicine.symptom ,business ,Breast reconstruction ,Indocyanine green - Abstract
Background: Indocyanine green angiography enables real-time visualization of blood vessels at depths of up to 10 mm beneath the body surface, thereby aiding the evaluation of the viability of skin flaps and predicting necrosis in surgical fields requiring good tissue perfusion. Although skin-flap necrosis also occurs in mastectomy without reconstruction, most studies have focused on reconstructive plastic surgery. Several patients undergoing mastectomy are eligible for postoperative adjuvant therapy, but complications can lead to delays in treatment and thus require prevention. However, a lack of a standard protocol for evaluating skin-flap perfusion using indocyanine green necessitates the study of its characteristics to facilitate comparison of the perfusion rate among individuals. Methods: This retrospective study focused on the characteristics of indocyanine green and established a protocol for indocyanine green angiography using laser-assisted imaging (SPY system) to predict postoperative skin-flap necrosis from intraoperative images of 30 patients who underwent mastectomy without reconstruction. Results: Our protocol predicted postoperative skin-flap necrosis as follows. First, the intravenous dose and concentration were set at 2.5 mg/mL and 0.05 mg/kg, respectively. Second, the timing of measurement was set to 100 s after the entry of indocyanine green into the skin (plateau phase); the analysis pattern was set to single frame. Third, comparisons among individuals were made using relative values. Conclusions: We analyzed the area of postoperative flap necrosis using this protocol. We found that the intraoperative images showed decreased perfusion in that area, which was useful in predicting skin-flap necrosis, as reported by previous breast reconstruction studies.
- Published
- 2021
21. [A Case of Pneumocystin a Patient with Pneumonia That Developed during Chemotherapy for Sigmoid Cancer]
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Hideaki, Murase, Hideaki, Iseki, Toru, Kikuchi, Ayumi, Ogawa, Kenichi, Kamachi, Akito, Mitsuoka, Mikiko, Hayashi, Park, Seongjin, Atsushi, Fukuuchi, Shinichiro, Kume, Youzou, Uryuuda, Kanako, Shinada, Shinichiro, Oota, Masahiro, Shinoda, and Masaharu, Shinkai
- Subjects
Male ,Sigmoid Neoplasms ,Pneumonia, Pneumocystis ,Humans ,Middle Aged ,Respiratory Insufficiency ,Tomography, X-Ray Computed - Abstract
A 63-year-old man was diagnosed with advanced sigmoid cancer of pT3, pN0, sM1c, sP3, fStage Ⅳ post-operation. After CAPOX plus Bmab as the first-line chemotherapy, he underwent IRIS plus Bmab as the second-line chemotherapy. After 1 course of IRIS plus Bmab, he was admitted to the hospital for fever, dyspnea, and general fatigue. The white blood cell count was 6.2×10 3/mL, and the C-reactive protein was elevated to 12.9 mg/dL. The PaO2 of the artery blood gas analysis in room air was 46.3 mmHg, suggesting respiratory failure. He was diagnosed with PCP based on the bilateral diffused ground-glass opacities on chest CT along with an elevated serum b-D-glucan. The treatment of trimethoprim-sulfamethoxazole and steroid was then initiated. After the patient's clinical condition improved, he was discharged on day 27 post-admission.
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- 2020
22. [A Case of Breast Cancer Complicated with Castleman's Disease]
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Yuichi, Kumaki, Tsuyoshi, Nakagawa, Momoko, Kasamatsu, Ayumi, Ogawa, Noriko, Hosoya, Goshi, Oda, Tomoyuki, Fujioka, Kazunori, Kubota, and Hiroyuki, Uetake
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Sentinel Lymph Node Biopsy ,Castleman Disease ,Axilla ,Humans ,Lymph Node Excision ,Breast Neoplasms ,Female ,Lymph Nodes ,Middle Aged ,Mastectomy - Abstract
The patient was a 57-year-old woman with Castleman's disease. The follow-up CT scans obtained during the treatment of Castleman's disease, detected a 15mm nodule in the right breast AC area, and the patient was diagnosed with breast cancer. Lymphadenopathy was noted on both sides of the axilla; however, it was considered to be due to Catsleman's disease. Mastectomy and sentinel lymph node biopsy were performed with preoperative diagnosis of cT1cN0M0, cStage Ⅰ. Rapid diagnosis of the sentinel lymph node during the operation showed a metastatic tumor measuring 3mm and axillary dissection was performed. However, no metastasis was found in the dissected lymph node, which was, therefore, considered as an enlargement due to Castleman's disease.
- Published
- 2020
23. Discovery of the novel HLA-B allele, HLA-B*51:01:01:36 in a Japanese individual
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Yosuke Omae, Yuki Hitomi, Ayumi Ogawa, Seik-Soon Khor, and Katsushi Tokunaga
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Sequence analysis ,Immunology ,Sequence Homology ,Biology ,chemistry.chemical_compound ,Asian People ,Polymorphism (computer science) ,Genetics ,Immunology and Allergy ,Humans ,Nucleotide ,Base sequence ,Allele ,Alleles ,chemistry.chemical_classification ,Polymorphism, Genetic ,Base Sequence ,Sequence Analysis, DNA ,HLA-B ,chemistry ,HLA-B Antigens ,Amino acid change ,sense organs ,5' Untranslated Regions ,DNA - Abstract
HLA-B*51:01:01:36 differs from HLA-B*51:01:01:01 by one nucleotide difference at position -230(G>T) with no amino acid change.
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- 2019
24. Predictors for upstaging of ductal carcinoma
- Author
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Goshi, Oda, Tsuyoshi, Nakagawa, Ayumi, Ogawa, Yuichi, Kumaki, Tokuko, Hosoya, Hitoshi, Sugimoto, Toshiyuki, Ishiba, Mori, Mio, Tomoyuki, Fujioka, Kazunori, Kubota, Iichiroh, Onishi, and Hiroyuki, Uetake
- Subjects
Articles ,skin and connective tissue diseases - Abstract
Preoperatively diagnosed ductal carcinoma in situ (DCIS) is sometimes upstaged to invasive cancer by postoperative pathological examination. Various preoperative factors associated with upstaging to invasive cancer have been reported; however, this subject remains to be clarified. DCIS takes various forms on imaging, but many cases show non-mass-type lesions. In non-mass-type DCIS, recognizing the presence of invasion is difficult. To investigate predictors associated with upstaging to invasive cancer more precisely, we examined only non-mass-type DCIS. The present study retrospectively analyzed 101 patients diagnosed with non-mass-type DCIS preoperatively on breast biopsy at our institution between 2007 and 2017. Data were analyzed using Fisher's exact probability test and two-sample t-tests. Multivariate analysis was performed using logistic regression. The results showed that 27 patients (27%) were finally diagnosed with invasive cancer. Univariate analysis revealed abnormal result of palpation on breast examination (P=0.05), comedo necrosis (P=0.05), and HER2 status (P=0.02) as significant predictors. Multivariate analysis revealed an abnormal result of palpation as an independent predictor of invasive cancer underestimation (odds ratio 4.76; confidence interval 1.44-15.7; P=0.01). In conclusion, preoperatively diagnosed non-mass-type DCIS represented an underestimation in approximately 27% of cases. In particular, the presence of a clinically abnormal palpation increases the chance of upstaging to invasive cancer.
- Published
- 2019
25. [A Case of Nephrotic Syndrome Due to SOX plus Bmab Therapy for Liver Metastasis of Rectal Cancer]
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Hideaki, Murase, Hideaki, Iseki, Ayumi, Ogawa, Kenichi, Kamachi, Akito, Mitsuoka, Mikiko, Hayashi, Park, Seongjin, Atsushi, Fukuuchi, Shinichiro, Kume, Yozo, Uriuda, Kento, Hirayama, and Kosuke, Negishi
- Subjects
Male ,Nephrotic Syndrome ,Rectal Neoplasms ,Antineoplastic Combined Chemotherapy Protocols ,Liver Neoplasms ,Humans ,Combined Modality Therapy ,Aged - Abstract
A 66-year-old man was postoperatively diagnosed with pT4a, pN2, cM1a(H2), cP0, fStage Ⅳ, RAS wild type rectal cancer. He underwent SOX plus Bmab chemotherapy 4 weeks later. After 9 courses of SOX plus Bmab, he was admitted to the hospital for leg edema and proteinuria(4+). Because of severe proteinuria(14.7 g/day)and low protein(Alb 2.0 g/dL, TP 4.9 g/dL), he was diagnosed with nephrotic syndrome. His general condition improved on stopping chemotherapy and administration of conservative treatment, and he was discharged on day 20 after admission. The proteinuria improved 3 months later. He had been undergoing SOX chemotherapy for 4 months.
- Published
- 2019
26. Usefulness of hysteroscopic intrauterine perfusion in frozen-thawed embryo transfer (FET) cycles
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Miho Takeuchi, Nao Mori, Chihiro Kondo, Ayumi Ogawa, Chika Uchimura, Kozue Hazeyama, Yumiko Nagai, Tokiko Iwakawa, and Kazuhiro Takeuchi
- Published
- 2018
27. [A Case of Rapidly Advancing G-CSF Producing Pleomorphic Carcinoma of the Breast Appearing as an Inflammatory Breast Cancer]
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Ayumi, Ogawa, Goushi, Oda, Takashi, Yasukawa, Yuuichi, Kumaki, Noriaki, Takiguchi, Keiko, Suzuki, Kouichi, Mori, and Tsuyosi, Nakagawa
- Subjects
Granulocyte Colony-Stimulating Factor ,Adenoma, Pleomorphic ,Disease Progression ,Humans ,Female ,Inflammatory Breast Neoplasms ,Aged - Abstract
We report a rare case of pleomorphic carcinoma of the breast, suspected of being a granulocyte-colony stimulating factor (G-CSF)producing tumor, in a 75-year-old woman. She presented with a red and swollen breast, 3 weeks after undergoing core needle biopsy(CNB). Her leukocyte counts and C-reactive protein(CRP)levels were markedly high. At first, she was suspected to have an abscess and was initiated on a course of antibiotics. However, her condition rapidly deteriorated; therefore, she underwent an emergency mastectomy. Despite undergoing postoperative radiation therapy, 2 months after the operation, multiple metastatic foci were found in the lungs and liver, and she died of the disease 3 months after her first visit. After the operation, her leukocyte count had quickly returned to normal, but it increased as the disease progressed. These findings support the conclusion that this carcinoma was producing G-CSF. The final pathological diagnosis was G-CSF producing pleomorphic carcinoma of the breast.
- Published
- 2018
28. セラミックス オ キーワード ニ シタ リコウケイ ジンザイ イクセイ カツドウ
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Kenji, Shida, Tomoaki, Hira, and Ayumi, Ogawa
- Published
- 2019
29. Periappendicitis during adalimumab treatment for ileocecal Crohn’s disease in a 29-year-old male
- Author
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Shinta Mizuno, Nobuhiro Tsukada, Tadakazu Hisamatsu, Shigemichi Hirose, Atsushi Nakazawa, and Ayumi Ogawa
- Subjects
Adult ,Male ,medicine.medical_specialty ,Exacerbation ,Anti-Inflammatory Agents ,Crohn Disease ,Surgical oncology ,Internal medicine ,Remission Induction Therapy ,medicine ,Adalimumab ,Humans ,Crohn's disease ,business.industry ,Gastroenterology ,General Medicine ,Ileitis ,Hepatology ,Appendicitis ,medicine.disease ,Colorectal surgery ,Surgery ,Typhlitis ,business ,Abdominal surgery ,medicine.drug - Abstract
A 29-year-old male was diagnosed with ileocolic Crohn's disease (CD) approximately 2 years ago. Adalimumab was prescribed as CD remission induction therapy. Three months after beginning adalimumab, watery diarrhea and lower abdominal pain developed. He was admitted under a diagnosis of CD exacerbation. Despite fasting and antibiotic treatment, symptoms of acute panperitonitis appeared. He was diagnosed as acute appendicitis and we performed emergency surgery for peritoneal drainage and ileocecal resection on the fifth hospital day. We diagnosed periappendicitis based on the operative findings. This is the first report of periappendicitis with CD during adalimumab treatment.
- Published
- 2015
30. A Case of Submandibular Lymphadenopathy with IgG4-related Disease
- Author
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Yoshinori Jinbu, Kei Kashimura, Yoshiyuki Mori, Akane Senna, Kazuo Komiyama, Naoyuki Matsumoto, Kimiharu Kikuchi, Mikio Kusama, Ayumi Ogawa, and Hiroto Ito
- Subjects
Pathology ,medicine.medical_specialty ,business.industry ,Submandibular lymphadenopathy ,Medicine ,IgG4-related disease ,business ,medicine.disease - Published
- 2015
31. PAPD5-mediated 3′ adenylation and subsequent degradation of miR-21 is disrupted in proliferative disease
- Author
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Chizuru Suzuki, A. Maxwell Burroughs, Ken-ichi Takayama, Yoshihide Hayashizaki, Carlos Rovira, Yoshinari Ando, Helena Persson, Rolf Søkilde, Akira Hasegawa, Shannon M. Hawkins, Kaoru Kaida, Satoshi Inoue, Piero Carninci, Michiel J. L. de Hoon, Kuniko Horie-Inoue, Inga Newie, Harukazu Suzuki, Joost Boele, Shintaro Aoki, Preethi H. Gunaratne, Marina Lizio, Ayumi Ogawa, Bas Teusink, Cristian Coarfa, Yuri Ishizu, Chihiro Sasaki, Jay W. Shin, Mizuho Sakai, and Kazuhiro Ikeda
- Subjects
Ribonuclease III ,Gene isoform ,RNA Stability ,Molecular Sequence Data ,Biology ,Models, Biological ,Cytosine ,IsomiR ,Neoplasms ,Exoribonuclease ,microRNA ,Gene Knockdown Techniques ,Humans ,Protein Isoforms ,Gene knockdown ,Multidisciplinary ,Base Sequence ,Adenine ,Gene Expression Profiling ,High-Throughput Nucleotide Sequencing ,RNA Nucleotidyltransferases ,Biological Sciences ,Molecular biology ,Gene Expression Regulation, Neoplastic ,Gene expression profiling ,MicroRNAs ,Exoribonucleases ,MCF-7 Cells ,biology.protein ,Nucleic Acid Conformation - Abstract
Next-generation sequencing experiments have shown that microRNAs (miRNAs) are expressed in many different isoforms (isomiRs), whose biological relevance is often unclear. We found that mature miR-21, the most widely researched miRNA because of its importance in human disease, is produced in two prevalent isomiR forms that differ by 1 nt at their 3' end, and moreover that the 3' end of miR-21 is posttranscriptionally adenylated by the noncanonical poly(A) polymerase PAPD5. PAPD5 knockdown caused an increase in the miR-21 expression level, suggesting that PAPD5-mediated adenylation of miR-21 leads to its degradation. Exoribonuclease knockdown experiments followed by small-RNA sequencing suggested that PARN degrades miR-21 in the 3'-to-5' direction. In accordance with this model, microarray expression profiling demonstrated that PAPD5 knockdown results in a down-regulation of miR-21 target mRNAs. We found that disruption of the miR-21 adenylation and degradation pathway is a general feature in tumors across a wide range of tissues, as evidenced by data from The Cancer Genome Atlas, as well as in the noncancerous proliferative disease psoriasis. We conclude that PAPD5 and PARN mediate degradation of oncogenic miRNA miR-21 through a tailing and trimming process, and that this pathway is disrupted in cancer and other proliferative diseases.
- Published
- 2014
32. TRIB1 downregulates hepatic lipogenesis and glycogenesis via multiple molecular interactions
- Author
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Yuumi Ishizuka, Kazuhiro Nakayama, Ayumi Ogawa, Saho Makishima, Supichaya Boonvisut, Atsushi Hirao, Yusaku Iwasaki, Toshihiko Yada, Yoshiko Yanagisawa, Hiroshi Miyashita, Masafumi Takahashi, and Sadahiko Iwamoto
- Subjects
Blood Glucose ,Male ,Blotting, Western ,Population ,Down-Regulation ,Protein Serine-Threonine Kinases ,Regulatory Sequences, Nucleic Acid ,Biology ,Polymorphism, Single Nucleotide ,Mice ,Endocrinology ,Genes, Reporter ,Non-alcoholic Fatty Liver Disease ,Enhancer binding ,CEBPA ,CEBPB ,Animals ,Humans ,RNA, Messenger ,education ,Molecular Biology ,Triglycerides ,Ultrasonography ,education.field_of_study ,Reporter gene ,Gene knockdown ,Lipogenesis ,Intracellular Signaling Peptides and Proteins ,Organ Size ,Molecular biology ,DNA-Binding Proteins ,Fatty Liver ,Liver ,Glycogenesis ,Gene Knockdown Techniques ,Female ,Energy Metabolism ,Transcriptome ,Glycogen ,Protein Binding ,Signal Transduction - Abstract
Mammalian tribbles homolog 1 (TRIB1) regulates hepatic lipogenesis and is genetically associated with plasma triglyceride (TG) levels and cholesterol, but the molecular mechanisms remain obscure. We explored these mechanisms in mouse livers transfected with a TRIB1 overexpression, a shRNA template or a control (LacZ) adenovirus vector. The overexpression of TRIB1 reduced, whereas induction of the shRNA template increased, plasma glucose, TG, and cholesterol and simultaneously hepatic TG and glycogen levels. The involvement of TRIB1 in hepatic lipid accumulation was supported by the findings of a human SNP association study. A TRIB1 SNP, rs6982502, was identified in an enhancer sequence, modulated enhancer activity in reporter gene assays, and was significantly (P=9.39×10−7) associated with ultrasonographically diagnosed non-alcoholic fatty liver disease in a population of 5570 individuals. Transcriptome analyses of mouse livers revealed significant modulation of the gene sets involved in glycogenolysis and lipogenesis. Enforced TRIB1 expression abolished CCAAT/enhancer binding protein A (CEBPA), CEBPB, and MLXIPL proteins, whereas knockdown increased the protein level. Levels of TRIB1 expression simultaneously affected MKK4 (MAP2K4), MEK1 (MAP2K1), and ERK1/2 (MAPK1/3) protein levels and the phosphorylation of JNK, but not of ERK1/2. Pull-down and mammalian two-hybrid analyses revealed novel molecular interaction between TRIB1 and a hepatic lipogenic master regulator, MLXIPL. Co-expression of TRIB1 and CEBPA or MLXIPL reduced their protein levels and proteasome inhibitors attenuated the reduction. These data suggested that the modulation of TRIB1 expression affects hepatic lipogenesis and glycogenesis through multiple molecular interactions.
- Published
- 2014
33. 小学6年生が持つ分数のmisconceptionに関する研究 ―分数の大小比較における行動に着目して―
- Author
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Ayumi,OGAWA and Tomohiko,MAKINO
- Abstract
text, 紀要論文 / Departmental Bulletin Paper
- Published
- 2013
34. The effects of ipragliflozin on the liver-to-spleen attenuation ratio as assessed by computed tomography and on alanine transaminase levels in Japanese patients with type 2 diabetes mellitus
- Author
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Hideo Kanehara, Kazuo Notumata, Kazuhide Ishikura, Azusa Hisada, Yukihiro Bando, Daisyu Toya, Kazuhiro Okafuji, and Ayumi Ogawa
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Endocrinology, Diabetes and Metabolism ,Spleen ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Diabetes mellitus ,Internal medicine ,Internal Medicine ,medicine ,biology ,business.industry ,Type 2 Diabetes Mellitus ,medicine.disease ,Surgery ,030104 developmental biology ,medicine.anatomical_structure ,Ipragliflozin ,Alanine transaminase ,chemistry ,biology.protein ,030211 gastroenterology & hepatology ,Original Article ,Hemoglobin ,Steatosis ,business ,Body mass index - Abstract
We assessed the effects of a 12-week ipragliflozin treatment on the liver-to-spleen attenuation ratio (L/S ratio) using computed tomography and on alanine transaminase (ALT) levels in Japanese patients with type 2 diabetes mellitus (T2DM). Sixty-two patients with T2DM [age, 56 ± 8 years; hemoglobin A1c (HbA1c) levels, 8.1 ± 0.9%; body mass index (BMI), 27.5 ± 3.3 kg/m2] were randomly assigned in a 2:1 ratio to receive ipragliflozin (50 mg/day; ipragliflozin group; n = 40) or continued treatment (control group; n = 22) for 12 weeks. The primary endpoints were changes in ALT levels; the secondary endpoints included changes in the L/S ratio and in the visceral fat area (VFA) and subcutaneous fat area (SFA) before and after 12 weeks of the treatment as assessed by computed tomography. ALT levels (−12.45 vs. +5.82 IU/l, P
- Published
- 2016
35. Positive natural selection of TRIB2, a novel gene that influences visceral fat accumulation, in East Asia
- Author
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Sadahiko Iwamoto, Yasuo Kagawa, Shogo Fukushima, Tetsuro Miki, Ayumi Ogawa, Katsuhiko Kohara, Kazuhiro Nakayama, Hiroshi Miyashita, Yasuharu Tabara, Tomohiro Onda, Michiya Igase, Mitsuhiro Katashima, Koichi Okada, and Yoshiko Yanagisawa
- Subjects
Linkage disequilibrium ,Candidate gene ,Allelic Imbalance ,Intra-Abdominal Fat ,Biology ,Polymorphism, Single Nucleotide ,Evolution, Molecular ,Asian People ,Gene Frequency ,Genetics ,Humans ,Thrifty gene hypothesis ,Selection, Genetic ,Allele ,Allele frequency ,Alleles ,Genetics (clinical) ,Asia, Eastern ,Haplotype ,Intracellular Signaling Peptides and Proteins ,Gene Expression Regulation ,Obesity, Abdominal ,Calcium-Calmodulin-Dependent Protein Kinases ,Selective sweep ,Genome-Wide Association Study - Abstract
Accumulation of visceral fat increases cardiovascular mortality in industrialized societies. However, during the evolution of the modern human, visceral fat may have acted as energy storage facility to survive in times of famine. Therefore, past natural selection might contribute to shaping the variation of visceral fat accumulation in present populations. Here, we report that the gene encoding tribbles homolog 2 (TRIB2) influenced visceral fat accumulation and was operated by recent positive natural selection in East Asians. Our candidate gene association analysis on 11 metabolic traits of 5,810 East Asians revealed that rs1057001, a T/A transversion polymorphism in 3'untranslated region (UTR) of TRIB2, was strongly associated with visceral fat area (VFA) and waist circumference adjusted for body mass index (P = 2.7 × 10(-6) and P = 9.0 × 10(-6), respectively). rs1057001 was in absolute linkage disequilibrium with a conserved insertion-deletion polymorphism in the 3'UTR and was associated with allelic imbalance of TRIB2 transcript levels in adipose tissues. rs1057001 showed high degree of interpopulation variation of the allele frequency; the low-VFA-associated A allele was found with high frequencies in East Asians. Haplotypes containing the rs1057001 A allele exhibited a signature of a selective sweep, which may have occurred 16,546-27,827 years ago in East Asians. Given the predominance of the thrifty gene hypothesis, it is surprising that the apparently non-thrifty allele was selectively favored in the evolution of modern humans. Environmental/physiological factors other than famine would be needed to explain the non-neutral evolution of TRIB2 in East Asians.
- Published
- 2012
36. High prevalence of an anti-hypertriglyceridemic variant of the MLXIPL gene in Central Asia
- Author
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Ayumi Ogawa, Ulziiburen Chimedregzen, Yasuo Kagawa, Sadahiko Iwamoto, Kazuhiro Nakayama, Lkhagvasuren Munkhtulga, Takafumi Ishida, Yoshiko Yanagisawa, Stevenson Kuartei, Yoshiro Koda, Somjit Supannnatas, Yuumi Ishizuka, and Phitaya Charupoonphol
- Subjects
Adult ,Male ,Population genetics ,Biology ,Polymorphism, Single Nucleotide ,Linkage Disequilibrium ,Young Adult ,Asian People ,Gene Frequency ,Genetic variation ,Prevalence ,Genetics ,Humans ,Genetic Predisposition to Disease ,Allele ,Carbohydrate-responsive element-binding protein ,Genotyping ,Alleles ,Triglycerides ,Genetics (clinical) ,Aged ,Hypertriglyceridemia ,Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ,Middle Aged ,MLXIPL Gene ,Genetic epidemiology ,Statistical genetics ,Asia, Central ,Female - Abstract
MLXIPL is a transcription factor integral to the regulation of glycolysis and lipogenesis in the liver. Common variants of the MLXIPL gene (MLXIPL) are known to influence plasma triglyceride levels in people of European descent. As MLXIPL has a key role in energy storage, genetic variations of the MLXIPL may be relevant to physiological adaptations to nutritional stresses that have occurred during the evolution of modern humans. In the present study, we assessed the phenotypic consequences of the Q241H variant of MLXIPL in populations of Asian and Oceanian origin and also surveyed the prevalence of Q241H variant in populations worldwide. Multiple linear regression models based on 2373 individuals of Asian origin showed that the H allele was significantly associated with decreased concentrations of plasma triglycerides (P=0.0003). Direct genotyping of 1455 individuals from Africa, Asia and Oceania showed that the triglyceride-lowering H allele was found at quite low frequencies (0.00-0.16) in most of the populations examined. The exceptions were some Central Asian populations, including Mongolians, Tibetans and Uyghurs, which exhibited much higher frequencies of the H allele (0.21-0.26). The high prevalence of the H allele in Central Asia implies that the Q241H variant of MLXIPL might have been significant for utilization of carbohydrates and fats in the common ancestors of these populations, who successfully adapted to the environment of Central Asia by relying on nomadic livestock herding.
- Published
- 2011
37. Abstract 4835: UD-017, a novel highly selective and orally active CDK7 inhibitor, shows a significant anticancer activity in patient-derived cancers
- Author
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Yasuhiro Aga, Shigeru Ushiyama, Ayumi Ogawa, Sayaka Ogi, Toru Hasegawa, Yasunori Tokunaga, Hidetoshi Sunamoto, Kazuhiro Onuma, and Takashi Matsushita
- Subjects
Cancer Research ,business.industry ,Colorectal cancer ,Cell ,Cancer ,Cell cycle ,medicine.disease ,medicine.anatomical_structure ,Oncology ,In vivo ,Cancer cell ,medicine ,Cancer research ,Sarcoma ,business ,Clonogenic assay - Abstract
Background: Cyclin dependent kinase 7 (CDK7) is an attractive target for anticancer drugs due to its dual roles, cell cycle regulation and gene transcription/RNA processing. We synthesized UD-017, a small-molecule, highly selective, orally active CDK7 inhibitor with a novel chemotype. In this study, we characterized anticancer activities of UD-017 in vitro and in vivo using patient-derived (PD) cancer cells. Methods: We first evaluated an antiproliferative activity of UD-017 broadly in a panel of cancer cell assay including patient-derived 3-dimensional tumor clonogenic assay. To verify the potential of c-Myc expression as a biomarker, we investigated the correlation between c-Myc expression levels and anticancer activity in vitro and in vivo using a colorectal cancer cell. In the main part, anticancer efficacy of UD-017 was investigated in vivo in PD-xenograft (PDX) models using representative PD cancer cells. Results: In antiproliferative panel assays using over 100 cancer cell lines, UD-017 broadly inhibited a wide range of cancer cells from colon, breast, lung, kidney, blood, pancreas, osteosarcoma, sarcoma and urinary bladder cancers. Especially, UD-017 showed high sensitivity in solid tumor such as non-small cell lung cancer (NSCLC), small cell lung cancer (SCLC), gastric, osteosarcoma and sarcoma cells with IC50s of 10-200 nM. UD-017 showed a good correlation of c-Myc expression levels with antiproliferative activity using colorectal cancer cells in vitro, and UD-017 reduced the intratumoral MYC mRNA levels by an administration at 100 mg/kg in a HCT-116 xenograft model in mice. In PDX models, UD-017 showed strong inhibition and even regression of tumor growth, and the tumors were almost disappeared on day 14 without body weight loss in non-small cell lung cancer (LXFL1121). In a pleuramesothelioma (PXF541) PDX model, UD-017 also showed regressive effect, and in gastric cancer (GXA3067) and sarcoma (SXFS117) PDX models, UD-017 completely inhibited the tumor growth. Conclusions: We propose UD-017 as a novel type of anticancer drug that shows complete antitumor responses in patient-derived xenograft models of diverse cancer types. c-Myc expression in cancer cells may be a biomarker for the antitumor effect of UD-017. These data support the rationale for further advancing towards clinical development. Citation Format: Takashi Matsushita, Sayaka Ogi, Kazuhiro Onuma, Hidetoshi Sunamoto, Ayumi Ogawa, Toru Hasegawa, Yasunori Tokunaga, Yasuhiro Aga, Shigeru Ushiyama. UD-017, a novel highly selective and orally active CDK7 inhibitor, shows a significant anticancer activity in patient-derived cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4835.
- Published
- 2018
38. Abstract 4837: Evaluation of anticancer activities of UD-017, a novel selective and orally available CDK7 inhibitor, in blood cancers
- Author
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Yasuhiro Aga, Takashi Matsushita, Sayaka Ogi, Shigeru Ushiyama, Toru Hasegawa, Hidetoshi Sunamoto, Noriaki Iwase, Ayumi Ogawa, Kazuhiro Onuma, and Shigeyuki Kono
- Subjects
Cancer Research ,biology ,Chemistry ,Cancer ,Cell cycle ,medicine.disease ,Peripheral blood mononuclear cell ,Oncology ,In vivo ,Cyclin-dependent kinase ,Cell culture ,Cancer cell ,biology.protein ,Cancer research ,medicine ,Cytotoxicity - Abstract
Background: Cyclin dependent kinase 7 (CDK7) is an attractive target for anticancer drugs due to its dual roles, cell cycle regulation and gene transcription/RNA processing. We synthesized UD-017, a small-molecule, highly selective, orally active CDK7 inhibitor with a novel chemotype. In this study, we characterized anticancer effects on blood cancer cells and in vivo anticancer activity in combination with chemo- or immuno-oncology agents. Methods: We first evaluated antiproliferative activities of UD-017 on blood cancer cell lines and investigated the mechanism of activity of UD-017 using NCI-H929 cells (multiple myeloma). Apoptosis was assayed by FACS analysis of Annexin V-positive and PI negative. In vivo anticancer effect was evaluated in the mouse xenograft model with NCI-H929. We further evaluated the anticancer efficacy of UD-017 in combination with chemotherapeutics in an HCT-116 xenograft mouse model and with anti PD-1 antibody in B16F10 mouse allograft model. Results: UD-017 strongly inhibited the proliferation of blood cancer cell lines (myeloma) with IC50s of 10-100 nM range, more broadly than other representative CDK inhibitors. In the similar assay, UD-017 showed no cytotoxicity to human peripheral blood mononuclear cells up to 10 μM. In the mechanism study, phosphorylation of RNA polymerase II c-terminal domain and expression of c-Myc were both inhibited concomitant with the antiproliferative activity in NCI-H929 cells. Significant apoptosis was induced at around 100 nM. In vivo, UD-017 almost completely inhibited the cancer growth at 50 mg/kg, q.d. for 14-day treatment in a NCI-H929 xenograft model in mice. In the combination assay in vivo, UD-017 showed a clear synergistic effect at 50 mg/kg with 5-fluorouracil (5-FU, 15 mg/kg, i.p.) without further affecting the side effects of 5-FU in HCT-116 (colorectal carcinoma) xenografted mice. Also, UD-017 (100 mg/kg) in combination with anti PD-1 antibody (250 μg/body, i.p.) showed add-on anticancer effect in B16F10-allografted mice. All of the mice in the combination group survived during the dosing period without decreasing the number of blood cells. Conclusions: We propose UD-017 as a novel type of anticancer drug that shows complete anticancer responses in xenograft models of myeloma cancer cells, and also shows in vivo synergy in combination with chemotherapy and anti PD-1 antibody. These data support the rationale for further advancing towards clinical development. Citation Format: Yasuhiro Aga, Sayaka Ogi, Kazuhiro Onuma, Hidetoshi Sunamoto, Takashi Matsushita, Ayumi Ogawa, toru Hasegawa, Shigeyuki Kono, Noriaki Iwase, Shigeru Ushiyama. Evaluation of anticancer activities of UD-017, a novel selective and orally available CDK7 inhibitor, in blood cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4837.
- Published
- 2018
39. Coupling Analysis of Atomistic and Electronic Structure of Single-walled Carbon Nanotubes under Tensile Deformation by TB-MD
- Author
-
Shigenobu Ogata, Yoji Shibutani, and Ayumi Ogawa
- Subjects
Materials science ,law ,Ultimate tensile strength ,Coupling (piping) ,Mechanical properties of carbon nanotubes ,Electronic structure ,Carbon nanotube ,Deformation (meteorology) ,Composite material ,law.invention - Published
- 2003
40. Abstract LB-111: In vitro anti-cancer activity of UD-017, a novel potent & highly selective CDK7 reversible inhibitor
- Author
-
Toru Hasegawa, Yasuhiro Aga, Sayaka Ogi, Shigeru Ushiyama, Shigeyuki Kono, Hidetoshi Sunamoto, Takashi Matsushita, Kazuhiro Onuma, Noriaki Iwase, and Ayumi Ogawa
- Subjects
Cancer Research ,Cyclin-dependent kinase 1 ,Cell cycle checkpoint ,biology ,Chemistry ,Kinase ,Cyclin-dependent kinase 2 ,Cell cycle ,XIAP ,Oncology ,Cyclin-dependent kinase ,Cancer cell ,Cancer research ,biology.protein - Abstract
Background: Cyclin dependent kinase 7 (CDK7) is a member of the CDK family, & has a dual function relating to the cell cycle progression & gene transcription/ RNA processing. Recently CDK7 has been emerged as an attractive target for anticancer drugs due to its dual role. We synthesized UD-017, a small molecule, highly selective CDK7 inhibitor with a novel chemotype. In this study, we characterized in vitro antiproliferative profile of UD-017 & elucidated underlying mechanism how CDK7 inhibition contributes to the antiproliferation of cancer cells. Experimental procedures: We conducted a large panel of 9 CDKs & 313 other kinases assay of UD-017 to determine its selectivity & analyzed kinetics for CDK7 enzyme inhibition. We evaluated the antiproliferative activity of UD-017 in over 100 multiple types of cancer cell lines. We then investigated the mechanism of antiproliferative activity of UD-017 using human colorectal cancer cell line, HCT-116, & human multiple myeloma cell line, NCI-H929. We also explored biomarker candidates mainly using colorectal cancer cell lines. Results: UD-017 inhibited CDK7 enzyme with an IC50 value of 16 nM, which is at least 300-fold more selective against other CDKs, CDK1 through CDK9. Inhibition of UD-017 was reversible & ATP-competitive. In a panel of 313 kinases assay, the compound inhibited CDK7 almost mono-specifically. In antiproliferative panel assays using over 100 cancer cell lines, UD-017 broadly inhibited a wide range of cancer cells from colon, breast, lung, kidney, blood, pancreas & urinary bladder cancers. Specifically, it inhibited the growth of HCT-116 & NCI-H929 with GI50 values of 29 nM and 6.8 nM, respectively. In the mechanism study of the antiproliferative activity, UD-017 inhibited phosphorylation of CDK1, CDK2 & the retinoblastoma (RB) & arrested the cell-cycle. Phosphorylation of RNA polymerase II c-terminal domain was also inhibited & expression levels of c-Myc and XIAP decreased & the cleavage of PARP increased, which were followed by significant induction of apoptosis. UD-017 showed both cell cycle arrest & induction of apoptosis. In the biomarker study, c-Myc & cyclin H showed good correlation with antiproliferative activities in 6 colorectal cancer cell lines and will be candidate biomarkers of UD-017. Conclusion: UD-017 is a potent & highly selective CDK7 inhibitor, & significantly inhibits the proliferation of human cancer cells with concomitant cell cycle arrest & induction of apoptosis. In vivo anti-tumor efficacy for UD-017 is warranted. Citation Format: Takashi Matsushita, Kazuhiro Onuma, Hidetoshi Sunamoto, Ayumi Ogawa, Sayaka Ogi, Toru Hasegawa, Shigeyuki Kono, Noriaki Iwase, Yasuhiro Aga, Shigeru Ushiyama. In vitro anti-cancer activity of UD-017, a novel potent & highly selective CDK7 reversible inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-111. doi:10.1158/1538-7445.AM2017-LB-111
- Published
- 2017
41. Abstract LB-297: In vivo anti-tumor efficacy of UD-017, a novel highly selective & orally available CDK7 inhibitor, in colorectal cancer cells xenograft models
- Author
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Yasuhiro Aga, Shigeru Ushiyama, Yasunori Tokunaga, Takashi Matsushita, Ayumi Ogawa, Hidetoshi Sunamoto, Kazuhiro Onuma, Toru Hasegawa, and Sayaka Ogi
- Subjects
Cancer Research ,Oncogene ,Colorectal cancer ,business.industry ,Retinoblastoma ,Cell cycle ,medicine.disease ,Oncology ,Pharmacokinetics ,Oral administration ,In vivo ,Cancer cell ,medicine ,Cancer research ,business - Abstract
Background: Cyclin dependent kinase 7 (CDK7) is an attractive target for cancer drugs due to its dual roles, cell cycle regulation & gene transcription/RNA procession. Recent studies show that transcription of some oncogene is highly sensitive to inhibition of transcription such as inhibition by CDK7. The dependence of cancer cells on transcription can be therefore advantageous to CDK7 inhibitors as effective anti-cancer drugs. We synthesized a novel small molecule highly selective reversible CDK7 inhibitor, UD-017. In this study, we evaluated anti-cancer activity of UD-017 in the colorectal cancer cells, HCT-116, xenograft models in mice & investigated the rationale for CDK7 inhibition as anti-cancer drugs. Experimental procedures: We first examined the pharmacokinetics profile of UD-017 after an oral administration in mice. We then evaluated the anti-tumor efficacy of UD-017 in HCT-116 xenograft models in mice. We further investigated the pharmacodynamics of UD-017 by detecting the phosphorylation levels of the retinoblastoma (cell cycle) & RNA polymerase II (transcription) & expression levels of c-myc in the tumor tissues in the same model after oral administration of UD-017. Results: UD-017 was identified as an orally available inhibitor of CDK7. The bioavailability was approximately 50% in BALB/c mice. In the HCT-116 xenograft model in mice, UD-017 inhibited the cancer growth by 33%, 64% & 88% at 25, 50 & 100 mg/kg, respectively, with clear dose-dependence by once daily administration for 14 days. Throughout the experiment, UD-017 was well tolerated with no reduction in body weights & no myelosuppression. In order to evaluate the effect of UD-017 in combination with chemotherapeutics, UD-017 was administrated with 5-fluorouracil (5-FU) to HCT-116 xenografted mice with either 50 mg/kg of UD-017 alone, or 15 mg/kg ip of 5-FU alone, or in combination of UD-017 plus 5-FU. UD-017 showed clear combination effect with 5-FU without further affecting the side effects of 5-FU. Phosphorylation of the retinoblastoma was inhibited after oral administration of UD-017 time-dependently in the tumor tissues. Phosphorylation of RNA polymerase II COOH-terminal domain (CTD) was also inhibited & expression of c-myc was decreased. PPAP cleavage was subsequently induced, causing apoptotic death of the cancer cells. Conclusion: We propose UD-017 as a novel type of anti-cancer drug that shows favorable oral pharmacokinetics profile & complete anti-tumor responses in xenograft models of colorectal cancer cells, & also shows in vivo synergy in combination with chemotherapy. These data support the rationale for further advancing towards clinical development. IND-enabling studies are in progress. Citation Format: Yasuhiro Aga, Sayaka Ogi, Yasunori Tokunaga, Ayumi Ogawa, Kazuhiro Onuma, Takashi Matsushita, Hidetoshi Sunamoto, Toru Hasegawa, Shigeru Ushiyama. In vivo anti-tumor efficacy of UD-017, a novel highly selective & orally available CDK7 inhibitor, in colorectal cancer cells xenograft models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr LB-297. doi:10.1158/1538-7445.AM2017-LB-297
- Published
- 2017
42. Preclinical in vitro and in vivo study of UD-017, a novel highly selective and orally available CDK7 inhibitor, in a variety of cancers
- Author
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Yasunori Tokunaga, Shigeru Ushiyama, Hidetoshi Sunamoto, Ayumi Ogawa, Takashi Matsushita, Yasuhiro Aga, Kazuhiro Onuma, and Sayaka Ogi
- Subjects
Cancer Research ,Messenger RNA ,Oncology ,business.industry ,Transcription (biology) ,In vivo ,Cancer cell ,Cancer research ,Medicine ,Cyclin-dependent kinase 7 ,business ,Highly selective ,In vitro - Abstract
e14086 Background: Cyclin dependent kinase 7 (CDK7) modulates mRNA transcription and some oncogenes are reported to be sensitive to inhibition of transcription in certain cancer cells. CDK7 inhibitors have been considered as an intriguing approach to treat cancers that depend on transcriptional regulation of their oncogenes. We synthesized a novel highly selective CDK7 inhibitor, UD-017, and found that the compound showed antitumor potency in a variety of cancers in vitro and in vivo. We therefore explored underlying mechanisms especially focusing on an oncogenic driver, c-Myc. Methods: We examined CDK7 selectivity of UD-017 against the other CDKs and kinases. We evaluated an antiproliferative activity of UD-017 in over 200 multiple types of cancer cell lines including patients-derived cancer cells. We then investigated the correlation between c-Myc expression levels and an antiproliferative activity of UD-017 in cancer cells. Antitumor efficacy of UD-017 was assessed in multiple types of cancer xenograft models and patients-derived xenograft model. We determined whether an intratumoral c-Myc expression levels correlated with in vivo antitumor efficacy of UD-017 in xenograft models. Results: UD-017 inhibited CDK7 enzyme (IC50= 16 nM) highly selectively among the CDKs (over 300-fold) and almost mono-specifically in a panel of 313 kinases assay. In a cellular antiproliferative panel assay, UD-017 broadly inhibited the proliferation of a variety of cancer cells and c-Myc expression levels showed the good correlation with antiproliferative activity. UD-017 showed favorable PK profile and good oral absorbability and showed the potent antitumor activity in multiple types of cancer xenograft models in mice. In correlation with the PK, UD-017 reduced the intratumoral c-Myc mRNA levels time-dependently after dosing of UD-017 in the colorectal cancer xenograft model. Conclusions: We identified a highly selective and orally available CDK7 inhibitor that showed the broad in vitro and in vivo antitumor activity in a variety of cancers, modulating c-Myc as an oncogenic driver. These data support the rationale for further advancing towards clinical development.
- Published
- 2017
43. Preclinical in vitro and in vivo evaluation of antitumor activity of UD-017, a novel selective and orally available CDK7 inhibitor, in colorectal cancer
- Author
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Yasunori Tokunaga, Yasuhiro Aga, Kazuhiro Onuma, Shigeyuki Kono, Tohru Hasegawa, Shigeru Ushiyama, Hidetoshi Sunamoto, Takashi Matsushita, Sayaka Ogi, Noriaki Iwase, and Ayumi Ogawa
- Subjects
Antitumor activity ,Cancer Research ,business.industry ,Colorectal cancer ,Cancer drugs ,RNA ,Cell cycle ,medicine.disease ,In vitro ,Oncology ,In vivo ,Cancer research ,Medicine ,Cyclin-dependent kinase 7 ,business - Abstract
e14085 Background: Cyclin dependent kinase 7 (CDK7) is an attractive target for cancer drugs due to its dual roles, cell cycle regulation and gene transcription/RNA procession. We synthesized UD-017, a small molecule, highly selective CDK7 inhibitor with a novel chemotype. In this study, we characterize antitumor activity of UD-017 in vitro and in vivo, and try to elucidate underlying mechanisms by which CDK7 inhibition contributes to the antitumor efficacy in colorectal cancer cells. Methods: We examined CDK7 selectivity of UD-017 against the other CDKs and kinases. We evaluated the antitumor activity in a variety of human cancer cell lines including colorectal cancer cells. We investigated the mechanism of antitumor activity of UD-017 using a human colorectal cancer cell line, HCT-116. In vivo antitumor efficacy of UD-017 was assessed in HCT-116 xenograft models and patient derived xenograft (PDX) model. Results:UD-017 inhibited CDK7 enzyme (IC50 = 16 nM), which is at least 300-fold more selective against other CDKs. In a panel of 313 kinases assay, UD-017 inhibited CDK7 almost mono-specifically. UD-017 potently inhibited the growth of human cancer cells including the patient-derived colorectal cancer cells.In the mechanism study, UD-017 inhibited phosphorylation of CDK1, 2 and retinoblastoma, which was followed by cell-cycle arrest. Inhibition of both RNA polymerase II phosphorylation and c-Myc expression was observed followed by apoptosis induction. HCT-116 xenograft model and PDX model demonstrated the potent antitumor activity of UD-017 with dose-dependence by daily oral administration for 2 weeks. Furthermore, UD-017 showed the combination effect with 5-FU without further affecting the side effects of the chemotherapy. Conclusions:UD-017 is a potent and highly selective CDK7 inhibitor, and significantly inhibits the growth of human cancer cell lines with cell-cycle arrest and apoptosis induction. UD-017 showed potent and dose-dependent antitumor response in the HCT-116 xenograft model and PDX model. Further investigation towards clinical development is warranted.
- Published
- 2017
44. Periodische Struktur eines einzelnen Blattes eines tuchartigen Makromoleküls - Untersuchung des 'atomaren Tuchs' mit Rastertunnelmikroskopie
- Author
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Masakazu Aono, Ayumi Ogawa, Mayumi Kasuga, Yasuhiro Mazaki, Daiji Fukushi, Hiroyuki Ozaki, Takao Tsuchiya, Tomohide Takami, and M. Uda
- Subjects
Materials science ,General Medicine - Published
- 1997
45. A single nucleotide polymorphism in the FADS1/FADS2 gene is associated with plasma lipid profiles in two genetically similar Asian ethnic groups with distinctive differences in lifestyle
- Author
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Ulziiburen Chimedregze, Shun Ishibashi, Lkhagvasuren Munkhtulga, Ayumi Ogawa, Takaya Gotoh, Kazuhiro Nakayama, Tumenbayer Bayasgalan, Yasuo Kagawa, Fumiko Tazoe, Sadahiko Iwamoto, Yoshiko Yanagisawa, and Kazuhiro Yamanaka
- Subjects
Fatty Acid Desaturases ,Linkage disequilibrium ,Genotype ,FADS1 ,Population ,Genome-wide association study ,Single-nucleotide polymorphism ,Locus (genetics) ,Biology ,Polymorphism, Single Nucleotide ,Linkage Disequilibrium ,Delta-5 Fatty Acid Desaturase ,Asian People ,Genetics ,Ethnicity ,Humans ,Allele ,education ,Life Style ,Genetics (clinical) ,Genetic Association Studies ,Triglycerides ,education.field_of_study ,Haplotype ,Cholesterol, HDL ,Cholesterol, LDL ,Lipids ,Haplotypes ,lipids (amino acids, peptides, and proteins) ,Genome-Wide Association Study - Abstract
Recent genome-wide association studies (GWASs) showed that single nucleotide polymorphisms (SNPs) in FADS1/FADS2 were associated with plasma lipid concentrations in populations with European ancestry. We investigated the associations between the SNPs in FADS1/FADS2 and plasma concentrations of triglycerides, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) in two Asian groups, i.e., Japanese and Mongolians. The genotype of rs174547 (T/C), found to be associated with triglyceride and HDL-C concentrations in the GWAS, was determined in 21,004 Japanese and 1,203 Mongolian individuals. Genotype-phenotype association was assessed by using multiple linear regression models, assuming an additive model of inheritance. The copy number of the rs174547 C allele was significantly associated with increased triglyceride levels (P = 1.5 x 10(-6)) and decreased HDL-C levels (P = 0.03) in the Japanese population. On the other hand, in the Mongolian population, the rs174547 C allele copy number was strongly associated with decreased LDL-C levels (P = 2.6 x 10(-6)), but was not associated with triglyceride and HDL-C levels. The linkage disequilibrium pattern and haplotype structures of SNPs around the FADS1/FADS2 locus showed no marked dissimilarity between Japanese and Mongolian individuals. The present data indicate that the FADS1/FADS2 locus can be added to the growing list of loci involved in polygenic dyslipidemia in Asians. Furthermore, the variable effects of FADS1/FADS2 on plasma lipid profiles in Asians may result from differences in the dietary intake of polyunsaturated fatty acids, which serve as substrates for enzymes encoded by FADS1/FADS2.
- Published
- 2009
46. Absorption of Organic Molecules on Alkali Metal-Graphite Intercalation Compounds
- Author
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Ayumi Ogawa, Hidekazu Sakuno, Noboru Akuzawa, and Yoichi Takahashi
- Subjects
chemistry.chemical_compound ,chemistry ,Intercalation (chemistry) ,Inorganic chemistry ,Thiophene ,chemistry.chemical_element ,Graphite ,Absorption (chemistry) ,Alkali metal ,Benzene ,Carbon ,Tetrahydrofuran - Abstract
Effects of starting carbon material (Heat-Treatment Temperature, 1000, 1500, 2000 and 2600°C) and chemical composition of K-GICs on the absorption of tetrahydrofuran (THF) and benzene (Bz) on potassium-graphite intercalation compounds (K-GICs) have been investigated by gravimetry and X-ray diffraction measurements. It is found that THF is absorbed on K-GICs, irrespective of the starting carbon material. On the contrary, benzene absorption is very sensitive to the degree of graphitization of the starting carbon material: No absorption was observed, except for K-GICs prepared from HTT-2600 carbon material. It is also found that as the composition of K-GICs, K/C, decreases, the absorbed amount, M/K (M denotes THF and benzene), increases. It is considered that the decrease of K/C results in the increase of interlayer free volume, where molecules are accomodated.Absorption of thiophene on cesium-graphite intercalation compounds (Cs-GICs) and on K-GICs prepared from natural graphite flakes were also investigated. Isotherms and effect of composition of Cs-GICs are determined.
- Published
- 1990
47. Periodic Structure of a Single Sheet of a Clothlike Macromolecule(Atomic Cloth) Studied by Scanning Tunneling Microscopy
- Author
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Daiji Fukushi, Tomohide Takami, Ayumi Ogawa, Hiroyuki Ozaki, Yasuhiro Mazaki, Mayumi Kasuga, Masakazu Aono, M. Uda, and Takao Tsuchiya
- Subjects
chemistry.chemical_classification ,Nanotechnology ,General Medicine ,General Chemistry ,Conductive atomic force microscopy ,Polymer ,Catalysis ,Electrochemical scanning tunneling microscope ,law.invention ,chemistry ,law ,Monolayer ,Scanning tunneling microscope ,Macromolecule - Published
- 1997
48. Electronic structure of single-walled carbon nanotubes under tensile deformation
- Author
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Yoji Shibutani, Ayumi Ogawa, and Shigenobu Ogata
- Subjects
Materials science ,Condensed matter physics ,Band gap ,Mechanical Engineering ,Nanotechnology ,Carbon nanotube ,Electronic structure ,Deformation (meteorology) ,law.invention ,Molecular dynamics ,Tight binding ,Mechanics of Materials ,law ,First principle ,General Materials Science ,Density functional theory - Abstract
Electronic states of single wall carbon nanotubes (SWNTs) under uniaxial deformation are analyzed using the tight-binding and first principle calculations. It is known as a curious and applicable phenomenon that the band gap drastically changes according to chiral vector which characterizes the geometric property of the SWNT. There are a few studies that have treated coupled behavior between mechanical and electronic properties. Most of the previous works have been determined the deformed atomistic structure by an empirical potential and then performed band analyses. This step-by-step process may have a possibility of making an error due to lack of transferability of the empirical potential at highly deformed state. In this study, in order to estimate electronic structure change more accurately, we used a tight-binding representation parameterized by Wang and et al. to relax the atomistic structure and estimate band gap simultaneously. We also performed more reliable first principle density functional calculations for the same models and estimated reliability of the tight-binding method.
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